Whether in the United States of America or elsewhere in the world, it is common practice to use an ornamental film which has a printed or vapor-deposited decorative surface and can be expanded three-dimensionally utilizing preformed slits or cutouts for adding an atmosphere of festivity to various occasions such as Christmas, New Year and Star Festivals.
As the base film for such an ornamental film, polyvinyl chloride film has heretofore been employed in most instances. The reason why polyvinyl chloride film is a virtually exclusive choice is that whereas films of other types tend to tear and break when expanded utiliting slits or cutouts, polyvinyl chloride film elastically resists such tearing forces.
However, under the current rigorous control over chemical substances for protection of the environment, polyvinyl chloride film cannot be disposed of by incineration, with the result that the user finds difficulties in disposing of the film when it is no longer needed or has become useless. Moreover, since polyvinyl chloride film is low-melting and flexible and contains large amounts of stabilizer, slip agent and other additives, it does not necessarily lend itself well to processing by vapor deposition.
Under the circumstances the inventors of this invention attempted to employ a biaxially oriented polyester or polypropylene film which can be incinerated without environmental hazards and is compatible with vapor deposition and comparatively inexpensive in lieu of polyvinyl chloride film but when slits or cutouts are formed in it, the film tends to develop fine tears when expanded three-dimensionally.
Having been conceived and developed in light of the above situation, this invention has for its object to provide an ornamental film which is less liable to tear even if it is formed with slits or cutouts, highly compatible with a vapor deposition process, disposable by incineration, and comparatively inexpensive.